Phased arrays are electromagnetic antenna systems that include a large number of antenna elements along with electronics connected to the antenna elements that perform beam forming. The antenna elements are typically positioned in an orderly grid within the antenna aperture.
When the phased array is in a receive mode, each of the antenna elements capture some portion of the Radio Frequency (RF) energy from incoming signals and convert the RF energy into separate electrical signals that are fed to the electronics. The electronics utilize reconfigurable gain and phase delays for the separate electrical signals in order to generate a spatial filter that strongly favors signals arriving from a specific direction. This favored direction represents the look angle of its beam, with the shape of the beam adjustable based on weighting factors applied to the separate electrical signals.
When the phased array is in a transmit mode, electrical signals generated by the electronics are fed to the antenna elements, which convert the electrical signals into radiant energy. The control electronics vary the phase relationship between the antenna elements such that radio waves from the separate antenna elements add together to increase radiation in a desired direction, while cancelling to suppress radiation in undesired directions.
One current solution utilizes relatively bulky and narrow-band waveguides having a circular cross-section to form the aperture of the phased array antenna. However, this and other existing solutions cannot meet ultra-wide bandwidth while scanning and other requirements for some applications that are currently being developed.
It is therefore evident that phased array antennas may be improved in order to support ultra-wideband applications that are in use today.